Improvement in steam-engine cylinders



UNITED STATES PATENT OFFICE.

SAMUEL D. GILSON, OF SYRAOUSE, ASSIGNOR TO HIlWISELF AND JOSEPH HALL, OF ROCHESTER, NEW YORK.

MPROVEMENT lN STEAM-ENGINE CYLINDERS.

Specification forming part of Letters Patent No. 39,527, dated August 11,1863.

To all whom it may concern:

Be it known that I, SAMUEL D. GrLsoN, of Syracuse, in the county of Onondaga and State ct' New York, haveinvented a new and useful Improvement in the Construction of Steam- Oylinders; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, making a part of this specica-tiou, in which- Figure l is a vertical central section of the cylinder, the piston-head and a section of the rod being shown in the elevation. Fig. 2 is a similar view, but showing a plain piston-head. Fig. 3 shows a short section of one half of a cylinder, having its inner surface perforated with a series of holes, instead of the annular channels shown in Figs. l and 2.

Similar letters of reference indicate correspondin g parts in the several iigures.

The nature of this invention consists in providing the inner surface of steam-cylinders with several annular channels, whereby the piston-head may be fitted loosely and the water and steam within the cylinder made to effect a perfect packing between the head and cylinder. The pressure of the steam behind the piston-head forms an eddy in each channel as it is uncovered by the receding piston, which eftectually prevents the steam from escaping around the piston-head, by causing a break or interruption in its tendency to establish a current. The piston-head is thereby rendered entirely effective, without incurring the enormous friction consequent upon the tight metallic packing ordinarily used.

To enable those skilled in the art to work my invention, I will proceed to describe its construction and operation.

My invention is applicable to the cylinders of all steam-engines, and may be :applied to those already in use, as its application consists simply in providing the inner surface of the cylinder G with the channels c, which may be done in any ordinary engine-lathe. The width and depth of these channels may be varied to suit circumstances, as may also the width of the space between them. The pistonhead D is turned three sixty-fourths of an inch (more or less) smaller than the bore ofthe cylinder. If the head is channeled, its channels may be made zigzag', as shown at a, Fig. 1, or, if they are made straight around, the space between them should either be wider or not so wide as between those of the cylinder, that there should never more than one of the channels of the former register to those ofthe latter at one and the same time. A plain head, as seen at D, Fig. 2, may be used, and,whether channeled or not, it should be long enough to cover two or more of the channels c, and may be made solid or of skeleton form. Instead of the channels c, the inner surface of the cylinder may be broken by drilling it full of holes, as seen in Fig. 3, about as deep as the channels c, FigsV l and 2.

I am aware it is not new to channel the piston-head of either steam or water cylinders, but the great advantage resulting from channeling the cylinder, instead of the piston-head, may be understood from the following suggestions: tlle channels in the piston-head are never uncovered 5 therefore, when once filled by the leakage between the cylinder O and head D they remain so, and offer little or no resistance to further leakage; whereas the channels c ofthe cylinder are each uncovered at every stroke of the engine, and as each is being uncovered by the receding head D, it forms an eddy or break in the passage of the steam, and prevents its escape past the pistonhead, thereby preventing the establishment of a current between the cylinder and piston-head, and

thus the necessity of tightly packing the piston-head, and consequently the enormous amount of friction resulting therefrom, is wholly avoided.

IVhat I claim as my invention is Providing the inner surface of steamcylinders with several annular channels c, or their equivalents, in combination with the pistonhead D, substantially as and for the purposes specified.

SAML. D. GILSON.`

Witnesses:

WM. S. LoUGHEoEoUeH. A. H. BILLINGs. 

